1. Field
Example embodiments relate to an apparatus and method of filtering a narrow band X-ray, and more particularly, to an apparatus and method of filtering a narrow band X-ray in which a plurality of micro filters configured in an array may be controlled to filter a broadband polychromatic X-ray to be a narrow X-ray.
2. Description of the Related Art
An X-ray may be widely used for obtaining medical information of a patient in a hospital, and for research purposes in a laboratory, or obtaining security information of passengers or goods in an airport.
A general X-ray generator used for generating the above-mentioned X-ray may have a structure in which electrons generated in a filament of a cathode are collided with a target of an anode to thereby generate an X-ray. The generated X-ray may be adjusted depending on materials and characteristics of a subject, and images may be created by the X-ray passing through the subject onto a detector installed behind the subject.
In general, an X-ray generated by the X-ray generator may be a broadband polychromatic X-ray. In the polychromatic X-ray, a strength of a radiation and an energy strength of light quantum may vary according to each of frequency bands. As a result, when photographing the subject using the polychromatic X-ray, there arise problems in that images of the subject may be not be clear due to a noise phenomenon of X-rays with different frequencies. Thus, optimum images based on the materials or characteristics of the subject may be not outputted, and an unnecessarily large amount of radiation may be irradiated to the subject. In particular, in the case of a human body, problems due to excessive radiation exposure may be generated.
Accordingly, there is a need for a filtering method corresponding to a specific monochromatic frequency or selecting only a narrow band X-ray in accordance with the monochromatic frequency.
As a method of filtering the narrow band X-ray, a method of using a graded multilayer coated-filter may be given. The graded multilayer coated-filter may apply coating with different thicknesses depending on a location of the filter, thereby selecting the narrow band X-ray. However, the graded multilayer coated-filter may need precision for coating with different thicknesses depending on the location of the filter, and a corresponding separate filter may be required to output a narrow band X-ray of another band.